* Astronomy

Blobrana · L

RE: A new light boson?

Blobrana · L

Title: A New Light Boson from Cherenkov Telescopes Observations?
Authors: Marco Roncadelli, Alessandro De Angelis, Oriana Mansutti

Early indications by H.E.S.S. and the subsequent detection of blazar 3C279 by MAGIC show that the Universe is more transparent to very-high-energy gamma rays than previously thought. We demonstrate that this circumstance can be reconciled with standard blazar emission models provided that photon oscillations into a very light Axion-Like Particle occur in extragalactic magnetic fields. A quantitative estimate of this effect indeed explains the observed spectrum of 3C279. Our prediction can be tested by the satellite-borne Fermi/LAT detector as well as by the ground-based Imaging Atmospheric Cherenkov Telescopes H.E.S.S., MAGIC, CANGAROO III, VERITAS and by the Extensive Air Shower arrays ARGO-YBJ and MILAGRO.

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Blobrana · L

Title: A new light boson from MAGIC observations?
Authors: Marco Roncadelli (1), Alessandro De Angelis (2), Oriana Mansutti (3) ((1) INFN, Sezione di Pavia, Italy, (2) Dipartimento di Fisica, Universita' di Udine, and INAF and INFN, Sezioni di Trieste, Italy, (3)Dipartimento di Fisica, Universita' di Udine, and INFN, Sezione di Trieste, Italy)

Recent detection of blazar 3C279 by MAGIC has confirmed previous indications by H.E.S.S. that the Universe is more transparent to very-high-energy gamma rays than currently thought. This circumstance can be reconciled with observations of nearby blazars provided that photon oscillations into a very light Axion-Like Particle occur in extragalactic magnetic fields. The emerging "DARMA scenario" can be tested in the near future by the satellite-borne Fermi LAT detector as well as by the ground-based Imaging Atmospheric Cherenkov Telescopes H.E.S.S., MAGIC, CANGAROO III, VERITAS and by the Extensive Air Shower arrays ARGO-YBJ and MILAGRO.

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